The number of teeth may vary between the male and female horses. If you want to know the answer to the question– how many teeth does a horse have, you are in the right place.
I will show you the exact number of teeth from the male and female horses with diagrams. Typically, you will find more teeth in a male horse than in females. Here, I will explain why male horses have more teeth than females.
Quick answer: a horse has 36 – 40 teeth in the lower and upper jaws. The males possess 40 teeth, whereas females have only 36 teeth in their jaws.
Sometimes, horses show 42 teeth due to one extra premolar tooth on the upper jaw. Again, the young horses possess less number of teeth (typically 24).
I will discuss these variations in the number of teeth of various horses. You will also get a full idea of the eruption of the teeth of a horse in its various ages.
How many teeth does a horse have?
The horse’s teeth are the hard white or yellowish-white structure implanted in the alveoli of the jaw bone. Morphologically the horse’s teeth are calcified papillae with prehension and mastication functions.
You will find the following types of permanent teeth in older horses –
- Incisor teeth – located in front and are implanted in the premaxilla and mandible,
- Canine teeth – located a little further back and interrupt the interalveolar space,
- Premolar teeth – forms the dental arch with the molar teeth and locates cranial to this arch, and
- Molar teeth – you will only find them in the permanent teeth, and they form the complete dental arch with premolar,
Both horses’ premolar and molar teeth are known as the cheek teeth.
If you count the number of teeth from the horse’s jaws (upper and lower), you will find the followings –
- Number of teeth in male horses – 40 (sometimes 42),
- Number of teeth in female horses – 36, and
- The number of teeth in a young horse – 24,
Let’s see the number of teeth from both young and older horses from Table 1 –
|Type of teeth||Deciduous||Male Horse||Female Horse|
Here, the number of incisors, canines, premolars, and molars express the teeth from one lateral aspect of the jaws. So, the number of teeth will be multiplied twice to get the permanent teeth from the older horses.
Horse teeth diagram
Let’s see the various types of teeth from the upper and lower jaws of the horses. I have identified various types of teeth from both upper and lower jaws with the diagram.
The basic structure of teeth from different animals is almost similar. I have already described the basic structure of the dog teeth along with their number in the below-mentioned article –
This article introduces you to the various parts of the teeth, like crown, neck, root, pulp, dentin, and others. Return to the equine teeth labeled diagram and identify the incisors, canine, premolar, and molars.
From the upper jaw of the male horse, I tried to show you the 6 incisors. There are 2 canine teeth in the upper jaw of male horses.
The diagram also shows 3 premolar and 3 molar teeth on each right and left half of the upper jaw. Thus, you will find 6 premolar and 6 molar teeth in the upper maxilla bone.
So, the total number of teeth in the upper jaw of the horses – 20 (permanent teeth).
The lower jaw of the male horses also shows a similar type and number of teeth. Thus, you will also find 20 teeth in the structure of the lower jaw or mandible of the horses.
Now, let’s count the teeth from the female horse’s jaws. Both the upper and lower jaws of the female horses show 18 teeth. Here, I tried to show the number and various types of teeth from the horse’s lower jaw with a diagram.
The deciduous teeth labeled diagram shows only 24 teeth. Let’s find more diagrams on equine teeth here.
Horse dental formula
The dental formula describes the number and arrangement of the various type of teeth. You know the dental formula of a horse comprises the abbreviation of I (incisor), C (canine), P (premolar), and M (molar).
Here, the formula expresses the number of corresponding permanent teeth on one side of the upper and lower jaws.
The dental formula for the permanent teeth (P) of the male horse is –
- Upper jaw = I3 C1 P3 M3 = 20;
- Lower jaw = I3 C1 P3 M3 = 20;
Or, you may also express the dental formula of a male horse as follow –
2(I 3/3 C 1/1 P3/3 M3/3) = 40
Again, some of the male horses show the following permanent dentition –
2(I 3/3 C 1/1 P4/3 M3/3) = 42
So, the horse occasionally has an extra pair of premolar teeth on the upper jaw. Then the total number of teeth for the male horses will be 42.
Dental formula for female horses or mare = 2 (I 3/3 P 3/3 M3/3) = 36
But the young horses have less number of teeth than the older ones. You may easily estimate the age of the horses with the help of the eruption of teeth. I will discuss the age estimation of the horses in the next section of this article.
The young horse has deciduous or milk teeth, known as temporary teeth. A permanent set of teeth replaces them.
These deciduous or milk teeth of the horses may find at birth or within a few weeks after birth. Let’s see the deciduous dental formula of the horses –
2(DI 3/3 DC 0/1 DP 3/3) = 24
Here, DI = Deciduous incisors, DC = Deciduous canine, and DP = Deciduous pre-molar.
Teeth of the horses (permanent and deciduous)
Table 2 will provide the summary of the number of the horse’s teeth –
|Type of teeth||Incisor||Canine||Premolar||Molar||Total|
The canine teeth of the female horse usually are very small. Or most of the time, the canine teeth in the female horse do not erupt. Thus the number of teeth reduces to 36 from 40.
Position, shape, and functions of various teeth
The dental formula of a horse shows 4 major types of teeth. Thus it is very important to understand and identify these teeth from the jaws.
Though the previously mentioned diagram might provide an overview of these various types of teeth. Now, let’s see the position, shape, and functions of 4 various types of teeth from the horse’s jaws –
Incisor teeth –
Position: lies in the incisive bone of the upper jaw and the mandible of the lower jaw
Shape: small, pointed with a single tooth,
Functions: fine nibbling and cutting, also used for delicate grooming,
Canine teeth –
Position: on each corner of the upper and lower jaws (incisive and mandible bones),
Shape: pointed with a simple curved shape, have a single root that is embedded deeply in the respective bones,
Functions: holding feed tightly and others,
Premolar cheek teeth –
Position: flatter surface with various points of the jaw bones (maxilla and mandible); cranially,
Shape: have pointed cusps or tubercles and possess two or more roots arranged in the triangular position,
Functions: shearing and grinding the feed or other substances,
Molar cheek teeth –
Position: within the alveolar sockets of the upper and lower jaw bones; caudally
Shape: have pointed cusps and tubercles and possess three more roots,
Functions: shearing and grinding the feed or other particles,
The information mentioned above on various teeth types might help you identify them perfectly.
How many incisors do horses have?
Horses have 12 incisors teeth in total. So both the upper and lower jaw of the horses possess 6 incisor teeth.
The six teeth on each jaw of the horse are placed close together. You will see the labial surface of these incisors form a semicircular edge.
The incisor of a horse possesses some peculiar features. Let’s see these peculiarities from the equine incisor teeth –
Structurally, the teeth possess a deep infundibulum (shown in the diagram) that becomes partly filled with cement,
These incisors of the horses have no cap of enamel on their crown (but the others possess this cap of enamel on the crown),
The horse incisor shows a central ring of enamel surrounding the deep infundibulum,
Again, you will also find a thin layer of peripheral enamel that surrounds the dentine,
The cavity or deep infundibulum darkens by deposits from the feed particles (known as the cup),
You will see the convex labial surface in each incisor of the horse,
The length of the equine incisor teeth varies with age. In the incisor from the permanent teeth, you will find the average total length of 2 – 3 inches.
Three major incisors are found in the horse’s upper and lower jaws. The type of incisors from the horse are –
- Center incisor teeth,
- Middle incisor teeth, and
- Corner incisor teeth,
These three incisors become tapered from the crown to the apex. Again, the cranio-lateral diameter near the apex is greater than the transverse diameter.
You may easily estimate the age of the horses by observing the appearance of the equine incisor teeth.
Why do male horses have more teeth than females?
The male horses have more teeth (40/42) than the females (36/38). This is due to the presence of one set of canine teeth in the male horse’s upper and lower jaws.
Here, I will show you 4 canine teeth from male horses. But the canine teeth are usually absent or rudimentary in female horses. In my study, I have not yet found any permanent or rudimentary canine teeth in female horses.
The canine teeth of the horses interrupt the interdental spaces. They divide the upper and lower jaws into unequal parts.
You will find the upper canine teeth at the junction between the premaxilla and maxilla bones. In contrast, the lower canine teeth are near the corner incisor teeth.
The horse’s canine teeth are smaller than the incisor and have a pointed structure. They are curved teeth with the concavity directed caudally.
The crown is compressed, and the edge of these canine teeth are sharp. Again, the embedded lower part of the horse’s canine teeth is rounded.
You will see a larger pulp cavity in the structure of the equine canine teeth.
The premolars and molars of the horses form the cheek teeth. You will see 24 premolars and molar (12+12) teeth in the horses.
You will find the common characteristics in the structure of these cheek teeth of equine –
They (cheek teeth) are very larger,
Prismatic in form,
Quadrilateral in the cross-section,
Three-sided (except the first and last teeth),
The crown of these check teeth are long,
Roots of the cheek teeth embedded into the maxilla and mandibular bones,
Upper cheek teeth
They are also known as the maxillary teeth embedded in the maxillary bone’s alveolar sockets. Here, the crown of these upper cheek teeth normally remains in close contact.
All these upper cheek teeth form a continuous row that is slightly curved. The long axis of the first upper cheek tooth directs upward and slightly forward.
Again, the long axis of the second cheek tooth of a horse is almost verticle. Others are curved backward, and the last cheek tooth shows strong curviness.
The average length of the upper cheek teeth for full-mouth horses is nearly 3 – 4 inches. You will find unique features in the buccal, lingual, and masticatory surfaces of the horse’s upper cheek teeth –
The buccal surface of the upper cheek teeth – presents a central ridge that separates two grooves,
The lingual surface of the upper cheeks – has a wide round ridge and accessory column, and
A masticatory surface of the upper cheeks – presents two infundibula (cranial and caudal),
The masticatory surface of the upper cheek teeth slopes obliquely downward and outward. You will find average one-inch width in the masticatory surface of these upper cheek teeth.
The first and last cheek teeth have three roots. Again, the reminder upper cheek teeth possess more than three roots.
Lower cheek teeth of the horses
The lower cheeks of the horses are also known as the mandibular teeth. They are located in the body of the mandible and form two straight rows.
You will find the similar length and direction of these lower check to the upper cheek teeth. But, the lower cheek teeth of the horses are embedded more deeply in the mandibular bone.
Here, the long axis of the first lower cheek tooth directs vertically. The remainder lower cheek teeth of the horse project ventrally and caudally.
The buccal, lingual, and masticatory surfaces of the lower cheek teeth also show unique features –
Buccal surfaces of the horse’s lower cheek teeth – have a longitudinal furrow (except the last cheek tooth),
Lingual surface of the lower cheek teeth – they are uneven and possess three or two irregular grooves, and
The masticatory surface of the horse’s lower cheek – is oblique and slope dorsally and medially,
The width of the lower cheek teeth’ crown is less than the upper molars. You will find two roots in the first five lower cheek teeth. In contrast, the horses’ sixth lower cheek teeth (last molar) show three roots.
Horse teeth age – eruption and aging of equine
It is better to know the horse’s birthday to know the actual age of your horse. But if you don’t know, then the eruption and wear of the lower incisor teeth may help to estimate the age.
But why I told you to estimate your horse’s age with the eruption of lower incisors? This is because of the accessibility of the lower incisor teeth. The upper incisors of the horse will increase difficulties without increasing accuracy.
To determine the age of a horse, you might examine whether the incisors are permanent or deciduous. If there are no permanent incisors in the lower jaw, the horse might be under 2 years.
Let’s see the overview of the age and eruption of deciduous teeth from Table 3 –
|Deciduous teeth||Express as||Eruption time|
|First incisor||DI1||Birth or first week|
|Second incisor||DI2||4 – 6 weeks|
|Third incisor||DI3||6 – 10 months|
|First premolar||DP1||Birth or within two weeks|
|Second premolar||DP3||Birth or within two weeks|
|Third premolar||DP3||During birth or 2 weeks|
Thus, you will only estimate the age of the young horse with the help of incisors. You will only find the first incisor and three premolars during birth or within the first week of age.
You will find the second premolar teeth within 4 – 6 weeks of age. Again, the third premolar teeth erupt at 6 – 10 months.
Summary: If no permanent incisor teeth exist, the horse’s age will be under 1.5 or 2 years.
Eruption of permanent teeth and estimate the horse’s age
The eruption time of the permanent teeth in various breeds of horses may vary. But I will provide an ideal eruption time of the permanent teeth here in Table 4. This might help you estimate the older horses’ age (age more than 2 or 2.5 years).
|Permanent teeth||Express as||Eruption time|
|First incisor||I1||2 – 2.5 years|
|Second incisor||I2||3 – 3.5 years|
|Third incisor||I3||4 – 4.5 years|
|Canine teeth||C (for male horse)||4 – 5 years|
|First premolar||P1||4 – 6 months|
|Second premolar||P2||2 – 2.5 years|
|Third premolar||P3||3.5 – 4 years|
|Fourth premolar||P4 (if it exists)||4 years|
|First molar||M1||9 – 12 months|
|Second molar||M2||2 years|
|Third molar||M3||3.5 – 4 years|
Thus, the eruption of the permanent incisor and molar might help you get a horse’s estimated age.
Teeth changes and aging of the horses
The structure and shape of the teeth become changes with age. To understand these changes in the horse’s teeth, you might be familiar with some terms –
In wear – this is the condition when the masticatory surfaces are in contact. And these surfaces are rubbing off the cementum and enamel to show dentin. This may occur approximately 6 – 8 months after the teeth eruption.
Let’s see the wear condition of the horse incisors –
- First incisor – at the age of 3 years,
- Second incisor – at the age of 4 years, and
- Third incisor – at the age of 5 years,
Level – it is very hard to see in live. This is the condition when the wear becomes flattened on the occlusal surfaces. You will see two enamel rings separated by dentin in this condition.
Cup gone – this is the condition when the infundibulum disappears. Let’s see the cup gone times for the horse incisors –
- First incisor – at the age of 6 years,
- Second incisor – at 7 years, and
- Third incisor – at 8 years,
Dental star – the staining of the teeth may appear at any age. So this is not the ideal point to estimate the horse’s age.
Round – refers to the shape of the occlusal surface, which becomes triangular. It means the transverse diameter is equal to the longitudinal diameter.
Cup gone for upper incisors – you may easily identify the cup gone for upper incisors. Typically at the age of 9 years, the cup gone for the first upper incisor occurs.
Triangular and rectangular conditions of the horse’s teeth
The triangular condition occurs when the longitudinal dimension becomes greater than the transverse dimension. Let’s see when a triangular condition occurs on the occlusal surface of the incisor teeth –
- First incisor – at the age of 16 years, and
- Second incisor of the horse – at the age of 17 years,
The enamel spot may disappear from the masticatory or occlusal surface of the incisor teeth between 14 – 16 years.
Rectangular – when the longitudinal direction is more than the transverse direction. The incisor teeth become rectangular at the age of 18 years.
Let’s see the counting and aging of the horse based on the teeth from Table 5 –
|Condition and teeth||Againg of horse|
|Deciduous (Full)||2 – 2.5 years|
|Deciduous (eruption)||Birth, 8 weeks to 10 months|
|Deciduous (in wear)||1 – 2 years|
|Permanent (incisor)||2.5 – 4.5 years|
|Wear (permanent teeth)||4 – 6 years|
|Cups gone (lower)||6 – 8 years|
|Cups gone (upper)||9 – 10 years|
|Triangular (incisor)||16 – 17 years|
|Rectangular (incisor)||18 years|
Incisor teeth of the aging horses
You will find a great change in the structure of the horse’s incisor teeth. Here, Table 6 will provide the summary of the changes in the incisors of the horses –
|Horse’s incisor teeth||Center incisor||Middle incisor||Corner incisor|
|Eruption||2 – 2.5 years||3 – 3.5 years||4 – 4.5 years|
|In wear||3 years||4 years||5 years|
|Level||5 years||6 years||7 years|
|Lower cup gone||6 years||7 years||8 years|
|Dental star||8 years||9 years||10 years|
|Upper cup gone||9 years||10 years||10 years|
|Triangular||16 years||17 years||16 – 18 years|
|Rectangular||18 years||19 years||21 years|
With the help of various conditions of the incisors, you may quickly estimate the age of a horse.
Frequently asked questions on the number of horse teeth
Now, I will enlist the learners’ most frequently asked questions on the number of horse teeth. But it is suggested to read the full guide to get the ideal knowledge on the number and types of horse teeth.
Let’s see the specific question on equine teeth with their concise answer –
How many teeth do female horses have?
Most of the female horses possess 36 permanent teeth. Sometimes you may find 38 permanent teeth in female horses.
The dental formula for the female horses is – (I 3-3/3-3 P 3-3/3-3 M 3-3/3-3) = 36
I have already discussed why female horses have less number of teeth than these of males. The structure and arrangement of these permanent teeth on female horses are almost similar (except canine).
Do horses have 2 sets of teeth?
Yes, horses have 2 sets of teeth. You will find the upper maxillary set of teeth which possess a larger cheek.
Again, another set of teeth locates on the body of the mandible. Thus, you may say, there are 2 sets of teeth in the horses –
- Upper–maxillary check teeth, and
- Lower–mandibular cheek teeth,
The arrangement and number of the various type of teeth in both upper and lower sets are almost similar in males. But the upper and lower set of teeth in female horses may show few dissimilarities.
I have already provided information on the types of teeth in both upper and lower sets in this article. Again, the difference between the male and female horse’s teeth is also shown previously.
Do all horses have teeth?
Yes, all horses, like young, older males and females, have teeth. But the number and arrangement of these teeth may vary.
Again, the time of eruption of various teeth like incisors, canine, premolar, and molar may also be different. The young horses have a greatly reduced number of teeth (only 24) compared to the older horses.
What are the special features of a horse’s deciduous teeth compared to the permanent set?
The deciduous teeth of the horses are smaller and fewer compared to the permanent set. You will find only the deciduous incisors and molars in the young horse.
There are no canine and premolar teeth found in the deciduous teeth. If there are canines, they may occur as the slender spicule. The lower canine may develop close to the corner incisor.
Again, the deciduous incisors are much smaller than the permanent set. You will find a distinct neck between the junction of the crown and root.
The crowns of the deciduous incisors are short, white in color, and possess smooth surfaces. You will find a shallow infundibulum in the deciduous incisors of the horses. The roots of these deciduous incisors are also flattened compared to the permanent set.
The deciduous premolar of the horses has a shorter crown than the permanent premolar. Again, the root of these deciduous premolar forms is early.
You will also find a distinct neck in the deciduous premolar of the horses. But the permanent molar or premolar has no distinct neck.
So I hope you got the perfect answer to the question – how many teeth does a horse have? The male horse has more teeth (40 – 42) than the female due to the presence of canine teeth.
The number of deciduous teeth of the horses is less (only 24) due to the absence of canine and molars. Major differences are found in the number and eruption time of the incisors between young and older horses.